"tugging fifth"

[jbergunder]

Hello,
We have a 23' Komfort 5th and have recently changed our tow vehicle from a 1995 GMC 3/4 ton long box to a 2008 GMC 3/4 ton short box. We had to have an axle flip done to accomodate the higher box height of the new truck.
Since the change we have noticed a tremeandous difference in the ride. The truck feels like it is being tugged back by the trailer over every little bump in the road. This was never the case with the old truck and trailer.
We thought the problem was with the trailer shock absorbers - they were removed when the axle flip was done - however - we reinstalled the shocks and the problem did not go away. The trialer bounces less but the "tugging" is still there. Our Dealer cannot come up with a reason.
Has anyone else run into this and if so did you find a cure?
We have been towing fifth wheels for many years and have never felt this tug before.
Thanks

[Frankenstien]

When the axles were flipped... were they "flipped", or were they moved below the springs and new pads welded on the axle. if they were moved (which is what should have happened) is is possible that the wheels are off camber, which will provide considerably more drag. If this is the case you will start to see some odd tire wear. An easy and quick way to check this is to take a piece of chalk or grease pencil, and mark a straight line from the inside edge to the outside edge of the tire, While the truck and trailer are in a straight line. Pull the truck forward 10-20 feet, then inspect where the wear is at. This will give you an Idea of how much camber you will need to add to the front or rear of the spring pad.

BTW Welcome to the Site!!!!!!

[Hitchhiker]

You might be able to get rid of the tugging by installing a Glide Ride pin box.

[Bailey47]

I use the Morryde rubber pin box on my 19,200lb fifth wheel. It does a great job of reducing the chucking action. I also have a Trailer Saver air ride hitch. This combo makes a great combo on my F450.

[Ray,IN]

This is just an EWAG, but here goes. You went from a long bed to a standard bed, right? Where is the pin center line when hitched? If it is directly above or behind the differential, this could contribute to the "tugging". Most 5er hitches call for 1"-3" in front of the differential. My Chevy K3500 LB,CC, dually, calls for directly above the differential, and I get some tugging on old pavement, wear patterns from big heavily loaded semis I guess.

[SilverBullet]

I have 3 questions below which are tied to this discussion...

My setup...
Truck: 2002 Chevy 2500HD crew cab short box
Hitch: B&W Companion mounted in center/high position
5'er: 2008 Keystone Cougar 289BHS (32 1/2')

I pulled my Cougar from Melissa, Tx to Broken Bow, Ok (approx. 165 miles) with a little fresh water (maybe 10-15 gals) in the tank for breaks. It bucked and tugged, and I was not happy with it.

On the return trip I put more water in the fresh tank and it pulled like a dream. Fresh water tank is behind the rear wheels on the 5'er. I drained and measured the water once home...it was between 40-45 gals (333-375 lbs, rougly).

I don't think I want to pull it with that much fresh water all the time as I can't see it being good for the trailer. (1) Is this correct?

On my hitch, I can move it 2" forward to the front/high position...(2) can 2" make that much difference?

(3) Would adding air bags to my truck help?

Thanks!

[RustyJC]

Quote:

Originally Posted by Hitchhiker You might be able to get rid of the tugging by installing a Glide Ride pin box.

The Glide Rite helped ours tremendously. It wasn't bad before, but it's almost totally absent now.

Rusty

[jbergunder]

Thanks to all for your tips. To answer some of your questions:
You are correct about the axle flip. Springs now mounted on top of axles. I will check the camber.
The hitch is mounted correctly - about 2" ahead of the rear axle.
I have never hauled much fresh water, but when I have there has been no difference in bounce. I will try that with this truck and see if it changes. My water tank is ahead of the trailer axles so will add weight to the front of the trailer - might settle the truck down.
I also noticed that my truck tire pressure is a few pounds high (5 psi) so will lower that on the next trip and see if it helps.
Thanks again for the tips - this is a great site!

[SilverBullet]

Right now the center of my hitch is 1/2 - 3/4" in front of the rear axle.

[450Donn]

My guess what you are experiencing is common when towing. Many combination's because of wheel bases will have this to one degree or another. I would suggest that if you could go back to your old truck the problem would be non existent. It is the wheel base difference between the old and new trucks causing the problem. The other big contributor can be slop in the hitch head to pin fit.

[SilverBullet]

I have 3 questions below which are tied to this discussion...

My setup...
Truck: 2002 Chevy 2500HD crew cab short box
Hitch: B&W Companion mounted in center/high position
5'er: 2008 Keystone Cougar 289BHS (32 1/2')

I pulled my Cougar from Melissa, Tx to Broken Bow, Ok (approx. 165 miles) with a little fresh water (maybe 10-15 gals) in the tank for breaks. It bucked and tugged, and I was not happy with it.

On the return trip I put more water in the fresh tank and it pulled like a dream. Fresh water tank is behind the rear wheels on the 5'er. I drained and measured the water once home...it was between 40-45 gals (333-375 lbs, rougly).

I don't think I want to pull it with that much fresh water all the time as I can't see it being good for the trailer. (1) Is this correct?

On my hitch, I can move it 2" forward to the front/high position...(2) can 2" make that much difference?

(3) Would adding air bags to my truck help?


Right now the center of my hitch is 1/2 - 3/4" in front of the rear axle.



Thanks!

[Ray,IN]

Silverbullet, It sounds like you found the answer to your tugging issue; traveling with a full tank of water. I nearly always have a full tank of water, I never know if we will stop at a CG for the night or at a wide spot in the road. To ease any hesitation, ask your dealer if a full tank of water will do harm to the unit.

As to moving the hitch 2", only a trial move can tell if it will improve towing. Trailer to cab distance must be watched closely.
Air bags_ donno. If your truck has original shock I would consder Bilstien or Rancho 9000 shocks for a replacement. Original shocks last about 20,000 miles, but you can't tell it when empty, only when loaded.

[SilverBullet]

Thanks Ray.

I did ask the dealer and they did not recommend running with a full tank all the time as the polyurethane tank has some give. They seem think it could stretch. I don't trust everything the dealer says...

Moving the hitch...you are right...test, test, test...this will be easy and luckily the worst stretch of road I have found is close to home!

I am running Bilsteins, but they may need to be refreshed with 186K on my rig. I have had Velvet Ride shackles on for many years, and never had any issues with pulling a comparable weight 20' gooseneck. They definitely help the ride while empty.

Since I have never used air bags, I am wondering how flexible they are...fill all the way up to get the most support (stiffer ride) or fill half way to get the support needed with a not as stiff ride...

SB

[450Donn]

What is the down the road actual as scaled weight of your trailer? Notice I am not asking for guesses. I will be really surprised if you are not over the trucks GVWR and possible the rear axle weight carrying that much trailer. If not over you are possibly quite close on your limits. How much does the rear of the truck drop when you place the pin weight on it? Air bags will only help get/keep the truck level when loaded. They will not increase your GVWR as posted on the drivers door post one pound.